Trauma-generated intrusive impaction of previously erupted teeth

Published: March 2012

Bulletin #9 - March 2012

Trauma-generated
intrusive impaction of previously erupted teeth

Typically,
the child is seated in the waiting area of the ER of a local hospital, holding
his bloodied mouth and face in a wad of Kleenex tissues. Mother is crying unconsolably
and the concerned father or perhaps the school teacher explains that the child
fell at school in the late afternoon and had knocked out his four upper front
teeth. The alert teacher had recruited the assistance of the boy’s classmates
and together they had made a search for the lost teeth, but could not find them
on the classroom floor/in the school playground/at the sports field or wherever
else the traumatic episode had occurred.

The
local hospital has no dental department per se and the duty oral and
maxillofacial surgeon is already at the golf course. The child is referred to a
local dentist and from there to a local pediatric dentist or perhaps another
OMFS and he is examined for the first time. A radiograph is taken and, to the
surprise of all concerned in this hypothetical scenario, it is found that the
teeth have not been knocked out, but have been pushed upwards into the alveolar
process, have become buried in the torn gingival tissues and all but lost from
sight. Moreover, a closer examination of the film shows that the teeth are
complete and their roots are not fractured.

Concurrently,
the oral tissues are bleeding profusely and, while hemostasis is relatively
easy to achieve, this is often a serious concern at the time due to its frightening
appearance. It is usually the least of the problems in the medium to long term
because oral tissues heal very well and very quickly – possibly with the help
of a few sutures in the lip or tongue.

As
with many of these emergency situations, the treatment advised may depend more
on this dental practitioner’s specialty or specific interest which may
influence what is perceived as being best for the patient. Thus, the pediatric
dentist is likely to suggest a period of waiting to see if the teeth will re-erupt
spontaneously, as has been described in a number of case reports. The OMFS may
recommend immediate surgical repositioning of the displaced teeth, followed by
fixed splinting. The generalist may prefer to call a colleague for further
advice, because it is not really his/her area - but it is now evening! The only
other person available is the orthodontist in the next office who is busy
straightening teeth after school hours.

When
incisor teeth are intruded in this manner – and it is almost invariably maxillary
incisor teeth - they are wedged upwards in a conical socket, which is narrowest
at the top end. In this type of traumatic displacement, the periodontal fibers
supporting them are more or less completely severed and the labial plate of the socket wall is fractured and displaced further labially to increase the width
of the sockets, driven by the wedging movement of the wider part of the tooth.
Essentially, the situation is one of a complete avulsion of the tooth, with
little or no periodontal fiber support, but the tooth remains in a blood-rich
environment and is thus at an advantage in comparison with a tooth that has
been totally avulsed, fallen out of the mouth and subsequently re-implanted.

TREATMENT

It
is now generally recommended to leave the teeth in place and hope for the
spontaneous re-eruption of the teeth that appears to occur in a fairly high
proportion of cases, while attending to the collateral damage that has occurred
to the soft tissues of the mouth and face. If reduction occurs in this way, it
seems that the long term damage will be less than will occur after active
reduction of the displacement.1-3

For
the most part, therefore, the treatment decision should be to wait for the
teeth to re-erupt spontaneously, but it is important to accept that not more
than a week or two should be allowed to elapse, since signs of re-eruption are
usually seen within a few days. If these signs are seen, then it is always
worth waiting for a further few weeks to obtain the maximum spontaneous benefit
available. It appears that the chances of resolution are better when the
affected tooth has an open apex. In the absence of early signs, reduction of
the displaced teeth needs to be made by alternative means.

The
surgical option

In
the surgical option for reduction of the impaction, it will be realized that
simply re-locating the teeth in their former positions does not take into
account the absence of a supporting socket wall, at least on the labial side
but possibly also on the palatal side. The fractured labial and/or palatal
process must also be re-located around the teeth and the gingivae sutured back
to close off the tissues. The teeth must then be splinted in this position
until their bony support has provided them with some stability. The danger is
that they may be easily displaced and lost, in the short term. The reader is
referred elsewhere for a fuller description of the techniques involved with the
surgical option and their relative merits.4

The
orthodontic option

Is
there an orthodontic option? The orthodontist is on hand, in that fateful
evening, to provide whatever assistance that may be indicated. The problem is
that he/she was taught in graduate school that, following trauma to the
anterior teeth, orthodontic treatment should not be started, or an ongoing
treatment be discontinued, for a period of 3-6 months after the teeth have
become symptomless and after any apical pathology has been resolved. On the
other hand, if he/she is to deny treatment to our hypothetical trauma patient
for this length of time, the chances of these teeth becoming ankylosed in this
position would be high, the teeth would be immovable and we would have a very
unhappy patient.

There
are also other dilemmas that may mitigate against considering an orthodontic
option. The teeth are almost completely buried in hemorrhagic gingival tissue
and one cannot possibly place brackets at the appropriate height, angle and
location without first performing gingival surgery. Furthermore, if we apply
extrusive traction to teeth whose periodontal fibers have been completely
severed from the surrounding bone of the socket walls, are we not likely to
find the teeth jangling loosely on our orthodontic wires in the patient’s
mouth, like some Amazon Indian’s trophy necklace, before we can say Jack Robinson!?

Notwithstanding
these important reservations, a good orthodontic option does exist and it
should be carefully considered, because it has advantages for the patient in
the long term.5

The
prerequisite is that nothing be done to move these displaced teeth in the
immediate post-trauma period, until a period of healing has passed, in which
some re-attachment of the severed periodontal fibers will have taken place and
until we have confirmed that signs of the hoped-for spontaneous re-eruption
have not appeared. This usually means waiting for a period of 2 to 3 weeks,
during which time debridement is carried out and the area cleaned with gentle
brushing and antiseptic mouthwashes. Antibiotics should be used, as deemed
necessary and the area maintained as free from infection as possible.

The
next task is to construct an appliance that is firm and rigid on the one hand,
yet able to apply a measurably light extrusive force to these teeth, either as
a group or, if necessary, individually. The following is a description of an
appliance that is recommended here.

The
appliance

I
know that you only have molar bands pre-welded with triple tubes and a hook,
but please try to find well-fitting plain (without pre-welded attachments)
molar bands and place them on the maxillary first molars. Take a “pick-up”
impression with the bands in place and then carefully remove the bands from the
teeth and re-locate them in the impression. Cast a model and have your
orthodontic technician solder a “cut-back” design palatal arch in 0.036”
stainless steel wire. Solder a round 0.036” buccal tube to the molars. An
0.036” self-supporting stainless steel labial arch is then fabricated on the
model, to lie a couple of millimeters labial to the anterior teeth/ridge and
parallel to the occlusal plane, when it is slotted into the buccal tubes on the
molar bands.5 The appliance is transferred to the mouth and tried
in, to check for proper fit, before cementing the bands and palatal arch in
place.

Now
comes the ticklish part! The minimum requirement for the intruded anterior
teeth is that a millimeter or two of their incisal edges are exposed. If one or
more of the teeth are completed covered by gingival tissues, then a very
conservative trimming of the gingival should be done to achieve this. A small
eyelet must now be bonded to this small exposed area on each of the teeth.

The
self-supporting labial archwire is replaced in the molar tubes and, in its
passive position should be such that it stands a few millimeters inferior to
the eyelets. Soft steel ligature wires are threaded through each of the eyelets
and secured around the slightly raised labial archwire. This will have
generated a light extrusive pressure, with a wide range, on the incisors and
the force exerted is easily measurable with a force gauge. The patient is seen
weekly over the next month or two, to renew the force, as the teeth respond to
the traction and until the teeth are relocated in their original positions.

In
the event that the teeth do not respond, it usually means that one or more of
them has established a bony connection and will need to be surgically
re-luxated. It only takes one of the teeth to be ankylosed for it to prevent
extrusive force being brought to bear on the others, if they are all ligated to
the labial arch. The re-luxation may be done immediately or it may be delayed
until the other teeth have reached their optimum locations, by separating the
presumed ankylosed tooth from the extrusion appliance.

It
is on record that when the intruded teeth have already completed their root
apexification, the chances of retaining vitality are virtually nil. With teeth
whose apices are still open, approximately half will recover their vitality, while
the remainder will become non-vital.3 However, there is plenty of
opportunity during this treatment period, from the day of the accident, to
consult with an endodontist or a pediatric dentist to decide what and when
endodontic treatment should be carried out. This is not merely a good idea,
this is one of the essential interdisciplinary decisions that must be taken
from the earliest opportunity after the accident and serially reviewed
throughout.

Fig. 1 a, b. Soft tissue lacerations were sutured on the day of the trauma and the patient was referred for orthodontic extrusion.

Fig. 2. Panoramic view of patient in early October 2009, immediately after the
trauma incident, showing the four maxillary incisors displaced high above the
occlusal plane, displaying no root fractures.

In the example that I have taken from my treatment files,
the boy was 12 years old and had received a blow to the front of the mouth,
which resulted in the total intrusive luxation of all four maxillary incisors
to gum level (Fig. 1). He first attended my office 5 days after the episode,
having been referred by a general dental practitioner and a pediatric dentist.
The incisal edges of the left central and lateral incisors were barely seen and
the same teeth on the right side were covered under the swollen and lacerated
gums. He was seen again 2 weeks later, in the absence of signs of spontaneous
eruption of any of the teeth.

Perhaps
the biggest potential problem, was that the fact that the parents were both
lawyers!! In fact, they turned out to be excellent, understanding, supportive
and model parents.

Fig. 3. The extrusion appliance consists of a palatal arch soldered to two molar
bands, with a removable steel self-supporting archwire, which slots into
soldered round cross-section buccal tubes.

Fig. 4a, b. Despite a post-trauma observation period of 3 weeks, no spontaneous
eruption was noted and active intervention was initiated in late October 2009.
Small eyelets were bonded to the exposed incisal edges of the 4 incisors, at
gum level and the archwire slotted into the molar tubes, seen here in its
passive position.

Fig. 4d. The anterior portion of the labial archwire has been raised (compare with
Fig. 3b above) and ligated to the eyelets, generating light extrusive force on
all four at once.

Molar
bands with soldered palatal arch, of the same design as noted above (Fig. 3),
were cemented into place and, after gently displacing the covering gingiva,
eyelet attachments were bonded to the incisal edges of the 4 incisor teeth
(Fig. 4). Light traction was applied immediately (Fig. 4d) and the patient
re-scheduled for follow-up 10 days later. The attachment on one tooth debonded
twice in the first week and had to be rebonded. During this time the child was
seen by his dentist on several occasions, to open the root canals of the
affected teeth and fill with calcium hydroxide paste.

Fig. 5a, b. Seen several times in the next month, the teeth did not respond to the
extrusive forces, but the banded permanent molars could be seen in November
2009 to be intruded and the palatal arch becoming buried in the palatal mucosa.
Ankylosis of one or more of the incisors was presumed.

After
2 visits and a gradual increase in the extrusive force, no progress was seen,
but it was noted that the palatal arch had become embedded in the palatal
tissue, with associated pain and swelling and the banded molars were intruded
(Fig. 5).

Fig. 6. It was unclear which of the teeth was responsible and the appliance was
arbitrarily separated from the right side incisors. In December 2009, the left
side incisors had erupted to occlusal level and the eyelets on the left side
and the labial arch were removed. The palatal arch was left in place for a
period of 3 weeksto permit the compressed,
swollen but asymptomatic palatal tissues to rebound and re-extrude the molar
teeth.

The
labial arch was removed for a week and then replaced to apply force only to the
left incisors, which erupted quickly (Fig. 6). When the same procedure was
adopted for the right side incisors, there was no response. However, the
maxillary first permanent molars had become intruded in relation to the
occlusal level of the teeth anterior to them and the palatal arch again became
embedded in the palatal mucosa. It was judged that ankylosis had occurred in at
least one of the teeth. To relieve the problem, the labial arch was removed for
3 weeks, by which time the molars had re-erupted and pressure on the palatal
tissue had subsided.

Fig. 7. In January 2010, the palatal arch was removed and re-cemented with an
acrylic Nance button added, to increase the anchorage value of the unit.
Traction was again applied to the right incisors but, this time, the teeth were
subjected to surgical luxation to facilitate their eruption by breaking the
presumed ankylotic connection to the alveolar bone.

The
molar bands and soldered palatal arch were removed and then replaced on the
same day with the addition of an acrylic Nance button (Fig. 7), to provide
improved and more comfortable resistance against the palatal tissue. There was
no response from the right central nor lateral incisors to elastic tie force
individually on each. Accordingly 4 weeks later, a local anaesthetic was
administered and these teeth were luxated with forceps until a considerable
mobility was achieved. They were reconnected to the labial archwire and immediate
extrusive force re-applied. Two further luxations were needed before the teeth
finally surrendered and then they moved very rapidly to reach the occlusal
level.

Fig. 8. By July 2010 and after 2 more surgical luxation procedures, followed by
immediate traction, all four incisors had erupted and regular orthodontic
brackets were substituted in their ideal locations on the teeth to achieve a
minimal degree of alignment. Three weeks later, appliances were removed, the
remaining deciduous teeth were extracted and a simple removable Hawley retainer
placed for a few months nocturnally, to maintain space until the premolars and
canines had erupted. No further orthodontic treatment has been performed since
this time. Root canal treatment with calcium hydroxide was performed on several
occasions over the period, by the general practitioner, once there was access
to the teeth from the palatal side.

With
normally displayed labial surfaces of all four incisors visible, orthodontic
brackets were substituted for the eyelets and left in place for 4 weeks to
achieve an acceptable alignment (Fig. 8). The appliance was removed (Fig. 8c)
and a simple removable retainer inserted in its place, the purpose of which was
to passively retain the achieved alignment and to maintain space posteriorly,
following the extraction of the remaining deciduous teeth. This was worn at
nights only for a further 4 months.

Trauma,
in general and ankylosis treated in this way, in particular, must be considered
strong candidates for future ankylosis to occur or recur. It is for this reason
that a reasonable alignment should be aimed for at this stage. However,
unnecessarily extending the duration of treatment to these teeth in order to
obtain “the perfect” alignment, is strongly ill-advised, since superfluous
manipulation may itself increase the risk.

Fig. 9. The July 2010 periapical and panoramic views of the dentition show the
temporary calcium hydroxide root fillings. They also show some foci of external
root resorption.

Fig. 10. Follow-up views of February 2012 show minor worsening of the resorption on
the right lateral incisor, but not elsewhere.

Follow-up should be turned over to those involved with the endodontic care
of the patient and their aim will be to try to minimize the type and severity of
root resorption that always accompanies teeth that have been traumatized in
this way (Fig. 9). Orthodontic follow-up and the consideration of whether to
undertake further orthodontic treatment should be decided in consultation with
the endodontist and there is no urgency in arriving at this particular decision
(Fig. 10) - indeed, delay may be beneficial in that it contributes additional
information regarding the prognosis of the affected teeth.

Fig.
11. Seen in February 2012, the alignment has improved markedly and
spontaneously, without resorting any form of appliance therapy. The teeth show
normal mobility and excellent gingival appearance. There is an unexplained
lateral open bite on the right side, which does not seem to be related to the
trauma episode. The advisability of offering orthodontic treatment for the
present condition will be reconsidered in a year’s time, following a
re-evaluation of the status of the root resorption.

It should always be remembered that the enemy of an
acceptable result (Fig. 11) may well be the aim to achieve a perfect result!

6.
Becker A. The orthodontic treatment of impacted teeth. 3rd edition. Oxford: Wiley Blackwell
Publishers, to be published March 2012

Acknowledgement:I thank Prof. Gideon Holen of the
Department of Pediatric Dentistry, Hebrew University-Hadassah School of Dental Medicine, Jerusalem, Israel,
for providing some of the answers regarding the pediatric/endodontic treatment
of traumatized teeth.